Refrigerating apparatus



J1me 1936- o. M. SUMMERS I 2,045,809

REFRIGERATING APPARATUS Original Filed Oct. 31, 1928 Patented June 30, 1936 PATENT OFFICE REFRIGERATING APPARATUS Otto M. Summers, Dayton, Ohio, assignor, by

mesne assignments, to General Motors Corpov ration, a corporation of Delaware Application Octoberfil, 1928, Serial No. 316,331 Renewed June 5, 1935 4 Claims. (01. 74-233 been major factors in belt design bec'ome minor factors and the belt structure may be directed more to providing transverse stiffness and longi- 10 tudinal flexure with long life at a lower cost.

The principal objects of the present invention are to provide a belt which will meet these conditions, and a, specific object is to provide a relatively thin V-shaped belt which will operate sat- 1 5 isfactorily on either a. grooved pulley or a flat pulley.

Further objects and advantages of the invention will be apparent from the following description, reference being had to the accompanying 2o drawing, wherein a preferred form of the invention is clearly shown.

In the drawing:

Fig. 1 is a side view of a belt embodying the present invention.

Fig. 2 is a perspective view of a dissected portion of the belt.

Fig. 3 shows a strip of fabricated material which is employed in making the belt.

Fig. 4 is an enlarged view of a portion of a modi- 30 fication of the belt shown in Fig. 2.

Referring to the drawing, I is an endless, vulcanized transmission belt, V-shaped in cross section. In the specific embodiment illustrated in Fig. 2, the inner and outer layers, II and I2 re- 35 spectively, are bias-cut, cross woven fabric, the

layer I3 is longitudinal thread fabric and the layer I4 is a relatively stiff rubber composition which may, if desired, contain unorganized cotton fibre.

In one method of making the belt shown in Fig.

40 2 the layers are plied as shown in Fig. 3, with the bias fabric layer I2 a continuation of layer I I and with the ends of the layers I I, I 3 and I4 staggered to make a better joint. The belt is then completed by winding the strip, beginning with 45 the end A, lengthwise on a drum to form a cylinder of fabric and nibber, vulcanizing the cylin der, and cutting the cylinder into raw-edgel belts. This is generally the process of the Short Patent 1,538,303 issued May 19, 1925. However, 50 in the present case, the fabrication can be done on a calender or table instead of directly on the canizing drum, which renders production easier d cheaper. w The modified form of belt shown in Fig. 4 is 65 the same as that shown in Figs. 2 and 3, except that the part A--B of the strip shown in Fig. 3

is made approximately twice as long so that the plied portion of the strip may be wound into two convolutions.

It has been found preferable to use a thin fab- 5 ricated or plied strip embodied into several turns in a cylinder rather than a strip composed of thick layers made up in a fewer turns. By way of example, I have obtained excellent results with a belt structure such as shown in Fig. 4, with the seven fabric and rubber layers of substantially uniform thickness embodied in a belt 45 inches long, 1 6 of an inch wide. on the inner surface, a

V angle of 38 and a thickness of approximately of an inch. This belt is especially adapted for usewith a grooved driving pulley and a flat driven pulley as shown in Hull Patent 1,648,178 issued .November 8, 1927.

Apparently the cementing together of a large number of thin fabric layers gives the thin belt the requisite high transverse rigidity, and ply separation is avoided by keeping the belt relatively thin and using both thin bias fabric and a thin layer of rubber for the filler portion. The use of a raw-edge" construction in a cut belt increases the side friction and promotes belt life.

It is obvious that many variations in the structure can be made and among them it may be noted that the side frictional surfaces may be increasedby using another turn of bias fabric, or decreased by leaving off one turn, as for example, the length AB or BC, Fig. 3,'and the structure of the load-carrying portionmay be changed without departing from the spirit of the invention; While it is well known that bias fabric may be 85 substituted for rubber filler, in the preferred construction both are employed.

While the form of embodiment of the invention as herein disclosed, constituted a preferred form, it is to be understood that other forms might/be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows.

' 1. A transmission belt formed of separate flat uniform single layers of bias fabric, cord fabric, and rubber filler strip and having a single separate layer of cord fabricprovided with a single separate layer of bias fabric upon one side and provided with a single uniform generally flat separate layer of rubber filler strip and a single separate layer of bias fabric on the. other side.

2. A transmission belt formed of separate flat uniform single layers of bias fabric, cord fabric,

and rubber filler strip and having the separate single layers arranged in the order of a single separate layer of bias fabric, a single separate layer of cord fabric, a single, separate fiat uniform rubber filler strip, a single separate layer of bias fabric, a single separate layer of cord fabric, a single separate fiat uniform rubber filler strip, and a single separate layer of bias fabric.

3. A raw edge transmission belt comprising a plurality of layers, said layers extending from one edge of the belt to the other edge thereof, each of said layers including a ply formed of bias fabric,

a ply formed of strip rubber, and a ply formed of longitudinally extending cords and interposed between the bias fabric ply and the rubber ply, said layers being superimposed upon one another with the bias fabric ply of one layer being adjacent the rubber ply of the other of said layers.

4. A raw edge transmission belt comprising a plurality of layers, said layers extending from one edge of the belt to the other edge thereof, each of said layers including a ply formed of bias fabric, a ply formed of strip rubber, and a ply formed of longitudinally extending cords and interposed between the bias fabric ply and the rubber ply, said layers being superimposed upon one another with the bias fabric ply of one layer being adjacent the rubber ply of the other of said layers, and said belt also having a covering ply disposed over and protecting the rubber ply of one of said superimposed layers.

OTIO M. SUIEMERS. 

